Increased risk of posterior circulation infarcts among ischemic stroke patients with cervical spondylosis

BACKGROUND Cervical spondylosis is one of the extrinsic factors causing vertebral artery stenosis. Several case studies have reported compression of the vertebral artery induced by cervical osteophytes that has resulted in posterior circulation infarcts (POCI). However, to the best of our knowledge, no studies have yet analyzed differences in the risk factors and stroke subtypes between ischemic stroke patients with cervical spondylosis and those without. PURPOSE In the case-controlled study reported here, we analyzed the risk factors and stroke subtypes in ischemic stroke patients with and without cervical spondylosis. Characteristics in all the recruited patients with POCI and non-POCI were further compared to extract other risk factors that could predict the occurrence of POCI. METHODS AND PATIENTS We filtered out ischemic stroke patients with cervical spondylosis ("Stroke+C" group) by International Classification of Diseases, Ninth Revision codes. We analyzed the data of 38 subjects in the Stroke+C group and 152 sex- and age-comparable ischemic stroke patients without cervical spondylosis ("Stroke-C" group). We recorded the demographic characteristics including sex and age, and stroke risk factors, including diabetes mellitus, hypertension, heart disease, hyperlipidemia, and smoking habits. The stroke classifications were defined by the Oxford Community Stroke Project classification. All subjects were further categorized into POCI or non-POCI groups. The ultrasound findings of the vertebral arteries (extracranial and intracranial) in the Stroke+C group were also recorded. RESULTS More patients in the Stroke+C group tended to have POCI (34.2%) than patients in the Stroke-C group (17.5%) (odds ratio [OR] =2.41, P<0.05). Furthermore, hypertension (OR=3.41, P<0.01) and cervical spondylosis (OR=2.41, P<0.05) were two independent risk factors for POCI in ischemic stroke patients. CONCLUSION Ischemic stroke patients with cervical spondylosis are more prone to POCI than those without cervical spondylosis. Hypertension is another identified risk factor for POCI in ischemic stroke patients. The occurrence of POCI should be highlighted for patients with cervical spondylosis.